5-nitro-2-aminobenzene-1-arsinic acid.



nrrnn STATES PATENT OFFICE.

LUDWIG BENDA. or I5RANKFORT-ON-TEIE-MAIN, GERMANY, ASSIGNOR T FARBWEBKE VORM. MEISTER LUcIUs & BRtiNING, OF HocHsT-oN-THE-MAIN, GERMANY, 4 con- PORATION OF GERMANY.

5-NITRO-2-AMINOBENZENE-LABSINIC ACID.

No Drawing.

To (117 whom if uU conccrn:

Be it known that l. Linwio BENDA. Ph. D. chemist. a citizen of the Empire of Germany. residing at Frauktort-on-the-Main. Germany. have invented certain new and useful Improvements in S-Xitro-Q-Aminobenzene-l-i\rsinic Acid. of which the followiugr is a specification.

I have found that by heating the paranitranilin with arsenic acid, the 5 -nitro-2 amino]renzenc-l-arsinic acid is obtained.

The new coi-upouml is of great value as a parent product for the manufacture of hith erto'. unobtaiuahle aromatic arsenic compounds which can be used for therapeutical purposes.

Example: kilos of arsenic acid are finely ground with 70 kilos of. para-nitrauilin and then heated on the oil-bath to about :1) C. The thick melt is then introduced into a solution of H liters of water and '20 kilos ot' sodium carbonate. The mass is stirred for some time and sodium carbonate added in order to continually maintain a strongly alkaline reaction. The solution isthen separated and saturated with common alt. After repeated filtration the solution is shaken out with ether in order to remove the dissolved nitranilin which may be present in small quantities. To the aqueous alkaline liquid is then added hydrochloric acid, whereby the 5-nitro-2aminobenzene-larsinic acid precipitates in the form of a luted acids.

Specification of Letters Patent. Patented Aug, 2'7, 1912, Application filed December 28, 1911. Serial No. 668,204. i

lemon-colored powder, which is filtered off, washed with cold water and'dried.

The new compound, which is only very difficulty soluble in cold water, can be recrystallized from boiling water. It' melts at 2352-6 C. while decomposing. Itis very readily soluble in alkalis, alkali carbonates, ammonia and sodium acetate, also soluble in the heat in methyl-alcohol and alcohol; it is very ditticultly soluble in the cold in di- When treated, with sodium nitrite and hydrochloric acid, ityields a readily soluble and scarcely colored diazo compound which easily combines with th various components of azo dyestuffs.

Having now particularly described my invention, what I claim is:

As a new product, the 5-nitro-2-amii obenzene-l-arsinic acid. being a lemon-colored compound, readily .soluble in alkalis, alkali carbonates, ammonia and sodium acetate. also soluble in the heat in methyl alcohol and alcohol, very diflicultly soluble incold diluted acids; yielding when treated with sodium nitrite and suspended in a solution of a mineral acid, a slightly-colored diazo compound.

In testimony whereof, I atlix my signature in presence of two witnesses.

LUDlVIG BENDA; Witnesses JEAN GRUN, CARL GRUND. 

